*{
    margin: 0;
    padding: 0;
}
body{
    text-align: center;
}

#list{
    display: inline-block;
    border: 1px solid #fff;
    border-right: none;
    border-bottom: none;
    height: auto;
    margin: 100px auto;
    overflow: hidden;
    background: url('/eightQueen/img/bg.jpg') 0 0 no-repeat;
    background-size: cover;
    /* border-radius: 50%; */
}
#list li{
    float: left;
    list-style: none;
    border: 1px solid #fff;
    border-left: none;
    border-top: none;
    text-align: center;
    background-size: cover;
}
#list li.active{
    animation:flash 0.5s infinite linear ;
    -webkit-animation:flash 0.5s infinite linear;
}
@keyframes flash{
    0%{
        opacity: 0.1;
    }
    50%{
        opacity: 1;
    }
    100%{
        opacity: 0.1;
    }
}